The present invention relates to a rotating laser device having an inclined laser plane. The invention also relates to a method for aligning a rotating laser device.
In order to perform leveling or marking jobs in interior and exterior areas, there are known rotating laser devices, which create limited or closed linear laser markings on a target surface. The tasks of the rotating laser devices include display of laser markings running horizontally or obliquely on a target surface.
Known rotating laser devices comprise a laser unit, which generates a laser beam, a rotational unit, which moves the laser unit at least partially about an axis of rotation at a rotational speed and a measuring unit with which the angle of rotation of the laser unit about the axis of rotation can be determined. Furthermore, known rotating laser devices have a leveling device, which aligns the laser plane in which the laser beam is rotated about the axis of rotation, independently of the housing alignment of the rotating laser device, to be parallel to a horizontal plane. The horizontal plane is aligned to be perpendicular to the gravitational field of the earth and is spanned by two axes running perpendicular to one another and known as the X axis and the Y axis. The leveling device comprises a first leveling unit for the X axis and a second leveling unit for the Y axis, such that the first and second leveling units each comprise a sensor device for monitoring the inclination and an adjusting device for adjusting the inclination.
To display oblique laser markings on a target surface, rotating laser devices have an inclination device with which the laser plane is inclined about an angle of inclination in a targeted manner in comparison with the aligned horizontal plane. These oblique laser markings are required in displaying a skewed plane, for example. It is important here that the laser plane is inclined in only one direction, which is referred to as the direction of inclination, and is still aligned horizontally in the direction, which is perpendicular to the angle of direction and is referred to as the horizontal direction. There are known inclination devices, which incline the laser plane about the X axis or about the Y axis. Inclination devices which incline the laser plane about the X axis as the axis of inclination are considered below, where the discussions can be applied similarly to inclination devices with which the laser plane is inclined about the Y axis. Rotating laser devices having an inclination device, which inclines the laser plane about the X axis and about the Y axis, are provided for other applications.
The inclination is adjusted in the leveled state of the rotating laser device, in which the laser beam is arranged in the horizontal plane. The alignment of the direction of inclination and that of the horizontal direction are defined by the measurement task, and the direction of inclination is aligned parallel to an X′ axis, which is displayed on the rotating laser device. In the ideal case, i.e., without any deviations in dimension between the components of the rotating laser device, the X axis, which is embodied as the axis of inclination, and the X′ axis, which is displayed on the rotating laser device, are parallel to one another, and the Y axis is arranged perpendicular to the displayed X′ axis and/or perpendicular to the direction of inclination. If the direction of inclination and/or the displayed X′ axis are arranged parallel to the axis of inclination (X axis) and perpendicular to the Y axis, then an inclination about the axis of inclination will not lead to an adjustment of the leveled horizontal position in the Y′ direction. Deviations in dimension between the various components of the rotating laser device lead to a rotation between the X axis and the X′ axis displayed on the rotating laser device and between the Y axis and the Y′ axis. If the direction of inclination is not arranged perpendicular to the Y axis, the inclination about the X axis leads to an adjustment of the leveled horizontal position in the Y′ direction, i.e., the horizontal direction deviates from the horizontal plane.
If the rotating laser device is rotated about the axis of rotation, there is an angular position in which the direction of inclination is aligned parallel to the X axis, which is embodied as the axis of inclination and perpendicular to the Y axis. Methods for manually aligning a rotating laser device which must be performed by an operator before any new measurement task of the rotating laser device with an inclined laser plane are known. The goal of these methods is to align the rotating laser device, so that the direction of inclination runs perpendicular to the Y axis. This position is determined by the operator in iterative steps. The operator has found the position being sought when a sensor device does not detect any adjustment out of the leveled horizontal position in Y′ direction with an inclination about the axis of inclination. It is a disadvantage that the known methods for aligning a rotating laser device are complex for the operator, so that the alignment is not always performed.
It would be desirable to improve upon the rotating laser device with regard to the disadvantages mentioned above. The object of the present invention is to reduce the complexity for aligning the rotating laser device for the operator and to increase the precision of the laser markings created by the rotating laser device on a target surface.
According to the invention, a memory unit is provided with the rotating laser device for storing at least one angular position. Due to the memory unit, there is the option of storing the angular position in which the direction of inclination is parallel to the X axis, which corresponds to the axis of inclination, and perpendicular to the Y axis, and there is the option of retrieving this angular position as needed, i.e., before a new measurement task. The effort for aligning the rotating laser device is reduced because the angular position need not be determined by the operator in a complicated procedure, but instead the rotating laser device need only be rotated into the angular position as needed.
A control unit, which adjusts at least one beam property of the laser beam as a function of the angle of rotation, is preferably provided. Suitable beam properties of the laser beam include in particular the laser power and, in the case of a modulated laser beam, the optical frequency and/or the amplitude. Due to the change in at least one beam property of the laser beam, there is the possibility of visually displaying the angular position for the operator.
In a preferred embodiment, the memory unit is embodied as a mechanical memory unit and is arranged in the form of at least one reference element on a master disk of the measuring device. The measuring device comprises a master disk which is connected to the rotational unit in a rotationally fixed manner, a scanning unit for scanning the master disk and a control and evaluation unit. The master disk is fixedly connected to a rotating shaft or is connected in a rotationally fixed manner by gear wheels or toothed belts. A fixedly attached master disk has the advantage that the measurement of the angle of rotation is stable with respect to external influences, in particular temperature. The resolution of the angle of rotation can be increased by adding a gear ratio as an intermediary function. A mechanical memory unit has the advantage that no additional component is necessary for the memory unit, and detection of the angular position is stable with respect to external influences.
In an alternative preferred embodiment, the memory unit is embodied as an electronic memory unit, such that the memory unit is especially preferably connected to an input device. An electronic memory unit has the advantage over a mechanical memory unit that the angular position in which the direction of inclination is aligned parallel to the X axis and perpendicular to the Y axis can be stored subsequently, so that rotating laser devices can be upgraded. Furthermore, there is the option of adapting the angular position to changing ambient conditions, if necessary. At the time of a repair or service on the rotating laser device, the manufacturer can check on whether the leveling axes and the axes of inclination are aligned as desired in the stored angular position. If this is not the case, the modified angular position can be determined by the manufacturer using measurement technology and stored in the electronic memory unit as a new angular position.
A display unit having a first display element and a second display element is preferably provided. The first display element is especially preferably embodied as a left arrow, and the second display element is embodied as a right arrow. The display unit has the advantage that adjustment instructions for the operator may be displayed by the display elements. A third display element, which indicates to the operator that the rotating laser device is arranged in the desired angular position, is especially preferred.
An automatic adjusting device is preferably provided, so that the rotating laser device is adjustable about the axis of rotation. This has the advantage that the alignment of the rotating laser device can be performed fully automatically and the effort for the operator is minimized.
A laser receiver is preferably provided, such that the laser receiver can be connected to the rotating laser device by a communication link, and the laser receiver is designed to determine at least one beam property of the laser beam and/or an interval of time of the laser beam. Through the combination of the rotating laser device with a laser receiver, there is the possibility of transmitting information about the laser beam to the rotating laser device.
According to the invention, in a method for aligning a rotating laser device, the angular position in which the axis of inclination is aligned parallel to a predetermined direction of inclination is stored in a memory unit. This method has the advantage that the angular position is already known and the rotating laser device need only be rotated into the corresponding angular position. The effort for the operator in aligning the rotating laser device is thereby reduced in that the operator need not first determine the angular position in a complicated procedure. The angular position need only be determined once in a complicated procedure and can then be used at any time to align the rotating laser device.
The laser beam is preferably moved about the axis of rotation at a rotational speed, an angle of rotation of the laser beam about the axis of rotation is detected by a measuring unit and at least one beam property of the laser beam is adjusted as a function of the angle of rotation. Due to the possibility of controlling the rotating laser beam, the stored angular position can be displayed visually on a target surface based on a changing beam property of the laser beam.
In a preferred variant, the at least one beam property of the laser beam is changed from a first value to a second value on reaching the angular position, and is changed from the second value to the first value on reaching the zero position. The operator recognizes the angular position as the position at which the laser beam changes its beam property. Due to the possibility of controlling the rotating laser beam, the stored angular position may be displayed visually on a target surface based on a changing beam property of the laser beam. The optical frequency of the laser beam is most especially suitable for doing this. Various optical frequencies may be generated by modulation of the laser beam at various modulation frequencies, for example. The beam property used may be any property of the laser beam, which is readily visible optically for the operator or can be detected with the help of a laser receiver.
In another preferred variant, a first angle of rotation, which is smaller than the angular position, and a second angle of rotation, which is larger than the angular position, are calculated from the at least one stored angular position, and at least one beam property of the laser beam is controlled as a function of the angle of rotation, such that the at least one beam property of the laser beam is altered from a first value to a second value on reaching the first angle of rotation, is altered from the second value to a third value on reaching the second angle of rotation, and is altered from the third value to the first value on reaching the zero position. This method has the advantage that the operator can recognize visually whether the rotating laser device is aligned, and if this is not the case, the operator can recognize whether a right rotation or a left rotation of the rotating laser device about the axis of rotation is necessary.
In an alternative preferred method, the laser unit is moved back and forth about the axis of rotation between a first and a second turning point by the rotational unit. In this scanning mode, the rotating laser device is aligned in the desired angular position when the midpoint of the limited laser line coincides with the direction of inclination of the rotating laser device.
The laser beam is preferably detected by a laser receiver and the at least one beam property of the laser beam and/or an interval of time is determined by the laser receiver. Adjustment instructions for the operator are preferably determined from the at least one beam property of the laser beam, such that the adjustment instructions are displayed on a display unit. Due to the fact that the laser receiver detects the at least one beam property of the laser beam that has been altered, the effort for the operator is further reduced. The operator receives simple adjustment instructions.
In an alternative preferred method, the at least one stored angular position is transmitted to an automatic adjustment device, and the rotating laser device is rotated by the adjustment device about the axis of rotation into the stored angular position. This variant of the method has the advantage that the alignment of the rotating laser device is performed fully automatically and the effort for aligning the rotating laser device for the operator is minimal.
Exemplary embodiments of the invention are described below with reference to the drawings. These drawings do not necessarily represent exemplary embodiments drawn to scale; instead, the drawings are in a schematic and/or slightly distorted form, where this serves the purpose of explanation. Reference is made to the relevant prior art with regard to supplements to the teachings directly discernible from the drawings. It should be pointed out that a variety of modifications and changes pertaining to the shape and details of an embodiment can be made without deviating from the general idea of the invention. The features of the invention disclosed in the description, the drawings and the claims may be essential by themselves individually and also in any combination for the further embodiment of the invention. Furthermore, all combinations of at least two of the features disclosed in the description, the drawings and/or the claims fall within the scope of the invention. The general idea of the invention is not limited to the precise form or the details of the preferred embodiment shown and described below, nor is it limited to an object that would be restricted in comparison with the object claimed in the claims. With given dimension ranges, values within the aforementioned limits should also be disclosed as limit values and may be used and claimed at will. For the sake of simplicity, the same reference numerals are used below for identical or similar parts or for parts with an identical or similar function.